NIR photothermal therapy using polyaniline nanoparticles

Developing a biocompatible and efficient photothermal coupling agent with appropriate size is a prerequisite for the development of near-infrared (NIR) light-induced photothermal therapy (PTT). In the present study, polyaniline nanoparticles (PANPs) with a size of 48.5 ± 1.5 nm were fabricated and exhibited excellent dispersibility in water by a hydrothermal method and further surface functionalization by capping with F127. The developed F127-modified PANPs (F-PANPs) had a high molar extinction coefficient of 8.95 × 108 m−1 cm−1, and high NIR photothermal conversion efficiency of 48.5%. Furthermore, combined with NIR irradiation at 808 nm and injection of F-PANP samples, in vivo photothermal ablation of tumor with excellent treatment efficacy was achieved. In vitro transmission electron microscopy (TEM) images of cells, methyl thiazolyl tetrazolium (MTT) assay, histology, and hematology studies revealed that the F-PANPs exhibit low toxicity to living systems. Therefore, F-PANPs could be used as PTT agents for ablating cancer, and the concept of developing polyaniline-based nanoparticles can serve as a platform technology for the next generation of in vivo PTT agents.